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A079209
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Number of isomorphism classes of associative commutative non-anti-associative non-anti-commutative closed binary operations on a set of order n, listed by class size.
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9
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0, 0, 3, 0, 0, 3, 9, 0, 0, 0, 3, 0, 0, 16, 39
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OFFSET
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1,3
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COMMENTS
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Elements per row: 1,2,4,8,16,30,... (given by A027423, number of positive divisors of n!)
First four rows: 0; 0,3; 0,0,3,9; 0,0,0,3,0,0,16,39
A079244(x) is equal to the sum of the products of each element in row x of this sequence and the corresponding element of A079210.
The sum of each row x of this sequence is given by A079245(x).
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LINKS
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003
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STATUS
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approved
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